The present disclosure relates to a power supply control circuit and an image forming apparatus, and more particularly to a technique to control power supply to a load.
Some of multi-functional image forming apparatuses, such as so-called multifunction peripherals, include a plurality of ports (connectors) for retrofitting optional apparatuses such as a post-processing apparatus and a paper cassette. The optional apparatuses connected to the respective ports of the image forming apparatus are different from each other in load capacity connected to the power source. Accordingly, in a power supply control sequence for turning on and off the power through a circuit for supplying power to the ports, a power-up sequence adapted for the optional apparatus having a largest load capacity is adopted for turning on the power, in order to prevent an inrush current to thereby suppress a malfunction originating from an excessive current. For turning off the power, a power-down sequence adapted for the optional apparatus that requires a longest time when turning off the power is adopted, because the optional apparatuses connected to the ports may include one that requires a certain time when turning off the power, for example for saving the latest status. In this respect, techniques to modify the power supply to the connected load according to the power consumption of the load have been known.